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2001 Prius brake and abs light with weird sounds

Discussion in 'Generation 1 Prius Discussion' started by Joseph O, Dec 2, 2014.

  1. Joseph O

    Joseph O Junior Member

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    Hey everybody I'm completely new to hybrids so I have no idea whats going on here. I have a 2001 Toyota Prius with 146k miles and its been running very good until some weird things started happening during the past couple of months. When I start it up, the brake light and abs light come on along with a steady high-pitched noise and grinding noise (sounds like ice being scraped). While the lights are on and the sounds are being made, the brake becomes very soft/"spongy" and goes down to the ground without much force at all (It usually always does this when I start it up and sometimes - but not very often - when I'm driving). Sometimes it all goes off and everything is normal again after about 10 mins, sometimes all day, and sometimes only after a minute or two (It usually does it on a cold start, but sometimes even if the engine is heated up, it does it).

    I had the brake pads & brake calibers replaced, new spark plugs put in, and checked all of the fluid levels (which were all fine) thinking that those things may have been the problem. After that, the sounds and lights stopped coming on and everything was normal for about a month, then the weird stuff came back again.

    I took it to a Toyota dealer and they said it might be a part called a brake actuator that needs to be replaced. I've been trying to do research about this, but people with the same problem are being told to do different things or get different parts so I don't know what part I actually need to get or what I need to do about it.

    Here are two videos of the weird occurrences; the first one is after a startup, the second one is while driving:





    I appreciate any help in advance!
     
    #1 Joseph O, Dec 2, 2014
  2. valde3

    valde3 Senior Member

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    I think sound comes from brake pump. But you should first get your fault codes read with Toyota hybrid capable scanner. Fault information stays in the memory even after light has cleared. If you want to read code yourself get techstream. Or you can read fault codes from warning light by using jumper wire. Brake + ABS + Cabin Alarm > no brakes =( | PriusChat shows tc and cg pins and has something about replacing brake pump. But if with Prius you should get techstream if you want to DIY anything it’s not expensive. If you have it you can first try to bleed brakes to test if it helps.
     
    #2 valde3, Dec 2, 2014
  3. Joseph O

    Joseph O Junior Member

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    So do I just go up to Toyota and ask them for all of the fault codes for my Prius? Or do I need to ask something specifically? And I definitely won't try to work on it myself though because I've never actually worked on a hybrid.

    Also, the brakes were bled while I was getting my new brake pads and calibers, and afterwards the brake was "hard" (I was barely able to push it down without using harder than normal force) as if it was kinda stuck. But do I need to bleed them yet again?
     
    #3 Joseph O, Dec 2, 2014
  4. valde3

    valde3 Senior Member

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    If they were properly bled before and it fixed it for some time but then it needs bleeding again then the real problem needs to be fixed. If you’re taking it to Toyota to get it fixed just get it there. I don’t really see point in first trying to find out problem here and then Toyota finding it again. But it would be nice to know what the problem was after it’s fixed.
     
    #4 valde3, Dec 2, 2014
  5. Joseph O

    Joseph O Junior Member

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    Its just that I wanted to see if the forums here could help me figure out what the problem is so that I didn't have to go pay an arm and a leg for diagnostics at Toyota, and so I could at least have some type of reasonable information to tell them before they tell me about some unrelated, expensive "problem".
     
    #5 Joseph O, Dec 2, 2014
  6. valde3

    valde3 Senior Member

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    I don’t really know US diagnostic charge system.

    But I think that its brake actuator. Really only other possibility that there is air in the brake system. If there is air in it either leaking somewhere or it wasn’t bled correctly before. If you end up replacing brake actuator it probably is expensive new so you may think about using used part.
     
    #6 valde3, Dec 2, 2014
    Last edited: Dec 2, 2014
    Joseph O likes this.
  7. Joseph O

    Joseph O Junior Member

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    Thats exactly what the head/master mechanic at Toyota told me. He said that air is being pushed through the brake system and its going to all four of the tires and after I showed him the videos above, he also said that it may be the brake actuator. Also, when I press down on the brake, I can actually hear the air in the brake system (it sounds like a faint whistle of wind blowing). So if thats the case, do I need to just have the brakes bled correctly by Toyota? Or do I need to replace the brake actuator? Or both?
    S
     
    #7 Joseph O, Dec 2, 2014
  8. valde3

    valde3 Senior Member

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    Maybe it only needs to be bled correctly. Maybe it has leak somewhere that needs to be fixed but if you haven’t needed to ad brake fluid probably not. Maybe it needs brake actuator.
     
    #8 valde3, Dec 2, 2014
  9. rlin78

    rlin78 Junior Member

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    I noticed that you mentioned the brakes was hard to push after you changed the brake pads. this is a classic indication of bad brake booster pump. There is also air trapped if you have spongy brake or the paddle goes all the way to the bottom. Depending on what happened first, you might have a leak and you let the brake fluid ran too low which introduced air into the system. Some first gen Prius including mine would develop a slow leak on the brake booster pump. I first noticed it at 40,000 miles and lasted until around 135,000 miles before the booster pump went bad. Before then, I had to top off the brake fluid periodically. Replacement of the booster pump is difficult and you will need a factory service manual and mini VCI/Toyota Techstream. You can search my posts replacing the brake booster, it took me about 12 hours to replace and I chose to push it in from the bottom to avoid having to touch the AC lines. It was messier, but got the job done.
     
    #9 rlin78, Dec 12, 2014
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